1. Technical Field
The present invention relates to a technique for ejecting liquid such as ink.
2. Related Art
When manufacturing an ejecting head ejecting liquid, there is a case where a hole is bored or a protrusion is provided by press processing in a metal flat plate (plate). For example, in a head of a printer disclosed in JP-A-2009-160786, a hole of an inlet port for introducing ink is formed in a plate-shaped cavity section. When forming such a hole by press processing, a dies is provided on one surface of a thin metal flat plate, a punch is pressed from the other surface, and the hole is formed by punching.
However, when pressing the punch on the flat plate, distortion or undulation (warpage) is generated on the surface of the flat plate due to generation of material flow in a periphery of the flat plate by pulling by the punch. This phenomenon remarkably appears as a thickness of the flat plate becomes thinner and there is a problem that a flatness of the flat plate is likely to be lowered.